The incidence of cancer is increasing among the elderly and little is known about continuing cancer care. Cancer has shifted from an acute disease with prompt resolution, usually death, to a chronic disease where long-term treatment increases survival time. Among the elderly, a portion of that survival may be spent with limitations in functioning. This research proposes to describe how a new cancer diagnosis, initial and continuing treatment, initiates or adds to limitations in self care, mobility, continence, cognition symptoms, and mental health of elderly patients and how these variables affect the involvement, reactions and mental health of family caregivers. This research examines the impact of the clinical course of cancer and its treatment upon elderly patients' needs for assistance, the involvement of their families, and the formal and informal costs of providing this care. This trajectory begins with a retrospective assessment of patient functioning 30 days prior to hospitalization, obtains staging data, initial treatment, and continues with observations of patients and their caregivers at 6, 12, 24, and 52 weeks. Twelve hundred and thirty-five patients will be accrued in order to assure that approximately 800 cases (200 cases of prostate, breast, colo-rectal, and lung cancer) will be retained at the end observation. This study builds upon our current work and extends knowledge by: l) examining how age, comorbidity, cancer site, stage of disease, and function, measured prior to the cancer diagnosis, relates to the aggressiveness of treatment and to subsequent limitations in self care, mobility, continence and cognition; 2) relating age, comorbidity, cancer site, treatment and functioning to the involvement of families in caring, their reactions, and mental health; 3) how incident cases of four cancer sites and their treatment are related to the formal system costs and informal costs born by families caring for these persons. The research proposed in this application is an essential "next step" in order to target the cluster of patient characteristics, cancer site and treatment variables, and management strategies for the design of cost effective interventions that will improve the functional outcomes for elderly cancer patients cared for by their families at home.